The gyroscopes sensors are, similarly to the accelerometer sensors,
assumed to be assembled in triads, and measure the angular velocity in
three orthogonal directions. Moreover, the gyroscopes are also assumed to
be calibrated in terms of scale factors, misalignment, and
cross-coupling [1]}.
Since the angular velocity is identical for all points on a rigid
body [2]}, the measurements from multiple geometrically
dispersed gyroscope triads can be fused to create an equivalent
virtual gyroscope
triad [3]}.
Hence, for the purpose of this work, it can without loss of generality
be assumed that there is only one
gyroscope triad in the inertial sensor array. The
measurements \(y_{n}^{(\text{g})}\)  from
the equivalent virtual gyroscope triad can be modeled as
\(y_{n}^{(\text{g})}&= \omega _{n} + b_{n}^{(\text{g})} + w_{n}^{(\text{g})},\\b_{n+1}^{(\text{g})}&= b_{n}^{(\text{g})} + w^{(b,\text{g})}_{n} .\) 
